The present invention relates to a card type semiconductor memory device and, more particularly, to a card type semiconductor memory device for storing a color interleaved analog image signal obtained using an image sensing element.
Generally, in an image sensing element for photographing a color still image, color filters of different colors (e.g., RGB: red, green, and blue) are arrayed in a Bayer matrix (checkerboard pattern) in units of pixels, and the luminance of an object image is detected at each pixel position.
A still image formed from the luminance values of the pixels is output as a color interleaved analog image signal made of analog signals which have amplitudes representing the respective luminance values and are discrete on the time axis.
Conventionally, for, e.g., a digital still camera apparatus, a scheme using, as a medium for storing a still image, a nonvolatile semiconductor memory for storing an analog signal as an analog value has been examined because a still image obtained with an image sensing element must be stored at a high speed.
As storage media of this type, card type semiconductor memory devices (e.g., memory cards) detachable from a digital still camera apparatus have also been proposed, through they store digital data. Card type nonvolatile semiconductor memories for storing analog signals have also been examined.
However, in such a card type semiconductor memory device for storing an analog signal, when analog signal lines and digital signal lines are mixed and connected in the connector of the card type semiconductor memory device, as shown in FIG. 9, a digital signal interferes with an analog signal, and noise mixes into a still image signal. Especially when the card type semiconductor memory device is compact, the influence of noise becomes more conspicuous.